THINK TANK; Yes, but Did Anyone Ask The Animals' Opinion?

The controversy came with the first daffodils in March, shortly after Peter Singer, the father of the animal rights movement, reviewed a reissue of the book ''Dearest Pet: On Bestiality'' (Verso), by the Dutch biologist Midas Dekkers, for Nerve, an online sex magazine. Three months have passed and still the sun has not set on the latest tempest surrounding Mr. Singer, the provocative author of ''Animal Liberation'' and a professor of bioethics at Princeton University's Center for Human Values.

Mr. Singer has received his share of human venom before this. Protesters have called him a Nazi for his view that in some cases infanticide and euthanasia are morally justifiable.

The furor this time concerns sex with animals.

In his review, titled ''Heavy Petting,'' Mr. Singer noted that almost all of the taboos on nonprocreative sex (taboos against homosexuality, oral sex, contraception and masturbation) have vanished. But one notable exception still stands: the taboo on sex with animals. ''Heard anyone chatting at parties lately about how good it is having sex with their dog?'' he asked. The persistence of the bestiality taboo, he wrote, reflects humans' ambivalence about animals. We know we are like them, but we think we are better, and so we want ''to differentiate ourselves, erotically and in every other way, from animals.''

Of course, the taboo does not prevent fantasies. Mr. Singer described the illustrations in Mr. Dekkers' book, including ''a 17th-century Indian miniature of a deer mounting a woman'' and a 19th-century Japanese drawing of a very busy giant octopus groping a woman. Nor is the taboo always effective in real life. Mr. Singer noted that some men have sex with hens, and certain people don't stop the family dog from making free with them, which occasionally leads to ''mutually satisfying activities.''

The moral problem with human beings' consorting with animals, Mr. Singer suggested, is not human indignity and depravity but rather cruelty to animals. But as he put it, ''Sex with animals does not always involve cruelty.'' And if cruelty is the problem, isn't raising them to kill them generally worse than coupling with them? The San Francisco Chronicle summed up Mr. Singer's position on animals thus: ''You can have sex with them, but don't eat them.''

The reaction was swift and prolonged. Some critics were appalled on behalf of humans, others on behalf of animals. And the headlines flowed -- ''Lock the Barn Door,'' ''Puppy Love,'' ' and ''The Love That Dare Not Bark Its Name.''

As word of Mr. Singer's review spread, the debate began to shift from cruelty to consent. Slate, an online magazine, said Mr. Singer hadn't explained ''how an animal can go about giving consent because, well, you know, animals can't talk.'' And the New Republic went further: ''If animals are entitled to the protection of what we today call human rights, isn't sex with them, absent consent, rape?''

Pretty soon animal rights groups began weighing in, from the president of the Animal Sexual Abuse Information and Resource Site, a group that fights bestiality, to the president of United Poultry Concerns Inc., a group based in Machipongo, Va., that stands up for the rights of domestic fowl.

Priscilla Feral, the president of Friends of Animals, wrote that ''bestiality is wrong for the same reason pedophilia is wrong.'' Gary Francione, who is, like Mr. Singer, one of the signers of the Declaration on the Rights of Great Apes, said Mr. Singer could no longer be trusted with the rights of apes.

There was one important exception. Ingrid Newkirk, the president of People for the Ethical Treatment of Animals, not only stood by Mr. Singer but also imagined a few perfectly innocent human-animal sex acts: ''If a girl gets sexual pleasure from riding a horse, does the horse suffer? If not, who cares? If you French kiss your dog and he or she thinks it's great, is it wrong? We believe all exploitation and abuse is wrong.'' But she added, ''If it isn't exploitation and abuse, it may not be wrong.''

Mr. Singer said the fuss over his review was largely ''hysterical'' and a big waste of time. ''This country is in the grip of a Puritan worldview,'' he added. When it comes to bestiality, the stakes are relatively small: while factory farming kills billions of animals a year, he said, human-animal sexual interactions involve only hundreds or thousands.

To some degree, the subject of bestiality represents the extreme edge of a larger discussion about whether animals have rights and what they are. But a legal is also issue at stake. In an essay reproduced at www.asairs.com, Piers Beirne, chairman of the department of criminology at the University of Southern Maine, in Portland, where he teaches a course on animal abuse, wrote that 24 states now have laws against bestiality, and seven more are considering them.

In Maine, he said, bestiality was once considered a crime against God and brought a sentence of 10 years of hard labor. The law loosened up after World War II. But now a bill before the Maine State Legislature proposes to recriminalize bestiality on the ground that it is cruel to animals and linked with domestic violence. The Bangor Daily News quoted Philip Buble, a man who came to testify, as saying that he often has sex with his dog-spouse, Lady Buble. ''In the eyes of God,'' he said, ''we are truly married.''

The main effect of Mr. Singer's review, Mr. Beirne said, will be the one that he intended: ''A subject which for centuries was taboo will now be out in the open.'' But something else has changed. Now when it comes to bestiality, the debate is not so much about what God wants as what animals want.